1. "Toko 90nen no Ayumi" (90 year history in Tokyo Department of Japan National Railway), Vo. 37, Tokyo Dept., Japan National Railway, 1987. p.360.
2. ON SUBMARINE FOUNDATIONS; PARTICULARLY THE SCREW PILE AND MOORINGS.
3. Screw pipe pile was firstly used for seaside pier at Margate, England in 1856. This method was also used in following similar seaside piers in England including Brighton West Pier opened in 1866. (Civil Engineering Heritage, Southern England edited by R.A. Otter, ICE, pp. 199–200, 1994).
4. According to the reference 9) p.118, mentioned below, "Screw piles, patented by Alexander Mitchell in 1833 and 1847, were commonplace although much of the sales impetus came from his license G. H. Saunders (1820–57). When Saunders died, his chief assistant Frederick Johnson took over and issued a pamphlet in 1862, only to die himself soon after. By September 1863, George Wells was advertising as 'successor to the late Frederick Johnson . sole licensee of Mitchell's patents' although from March 1862 onwards Joseph Emerson Dowson was also advertising as a producer and became well-known as a supplier for seaside piers."
5. J. G. James. Overseas railways and the Spread of Iron Bridges, c.1850-70, 1987, pp.6–9, 83–85.